Single-branched olefins

The products of the ZSM-5 reaction in the gasoline boiling range are mainly C -C single branched olefins which have high Resesirch and Motor Octane, as illustrated below ... 

Scheme 2. Isomerization of organoboranes derived from singly branched olefins.

Blumer M (1970) Dissolved organic compounds in seawater. Saturated and olefinic hydrocarbons and singly branched fatty acids. In Hood DW (ed) Organic matter in natural waters. Publication no. 1. Institute of Marine Science, University of Alaska, pp 153-167... 

The aliphatic mono-olefins present a particularly complicated picture at first sight. Only a few of them will give high polymers by cationic catalysis most of these are either 1,1-disubstituted ethylenes, or ethylenes with a single branched substituent, such as 3-methylbutene-1 and vinylcyclohexane. The reasons why ethylene, propene, and the n-butenes do not give high polymers have been set out in detail [71]. Briefly, the ions derivable directly from all of these are either primary or secondary, e.g.,... 

To understand the reaction pathways, the yield shifts for the three examples illustrated in Table III were calculated on a fresh feed basis (Table V). These data show that the predominant reaction is the loss of C + paraffins and olefins. Approximately 2.5 wt 95 C + paraffins plus olefins were lost for a +1.5 Research Octane numoer increase. ZSM 5 is selective to cracking both single branched and linear paraffins, and single branched and linear olefins (9) which have very low Research and Motor Octanes, as illustrated below ... 

Organoboranes derived from internal acyclic olefins by hydroboration with BH3 undergo thermal isomerization at elevated temperature (100-160 °C). The Boron atom readily moves down the chain, past a single branch, but not past a quaternary carbon atom [1]. 

The nickel aminobis (imino) phosphorane catalyst polymerizes linear and singly branched a-olefins to... 

Olefin metathesis [1], having recently experienced precipitate development [2], is being applied increasingly for the preparation of a significant number of monomers for the plastic and rubber industries, either in a single step or in conjunction with other traditional hydrocarbon processes. Of these monomers, simple linear and branched olefins are of importance, the latter offering a new source for synthesis of common dienes used in the rubber industry. In addition, the metathesis reaction opens nonconventional ways for manufacturing certain particular aromatic or cyclic olefins. 

Linear terminal olefins are the most reactive in conventional cobalt hydroformylation. Linear internal olefins react at less than one-third that rate. A single methyl branch at the olefinic carbon of a terminal olefin reduces its reaction rate by a factor of 10 (2). For rhodium hydroformylation, linear a-olefins are again the most reactive. For example, 1-butene is about 20—40 times as reactive as the 2-butenes (3) and about 100 times as reactive as isobutylene. 

The catalytic single-step Alfen process has a good space-time yield, and the process engineering is simple. The molecular weight distribution of the olefins of the single-step process is broader (Schulz-Flory type of distribution) than in the two-step Alfen process (Poisson-type distribution) (Fig. 2). As a byproduct 2-alkyl-branched a-olefins also are formed, as shown in Table 6. About... 

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